So, it does sound feasible to be "on call" and not be able to leave the area and still use up your 3 weeks of leave time for only a few hours work now and then or not at all. Bummer, if your family and friends are across the country and you hoped to be home for the holidays. It's not so much that it is Christmas, but that it is 3 weeks of vacation time planned to visit family gone. We cannot visit our soldier because at our end, one of us is also on-call for a hospital. No drinking or traveling allowed. Also no pay received if not called in or all the work is done over the phone, even if the calls come in the middle of the night. Ho Ho Ho, indeed.
Sorry if I am a bit bummed out... At least police, bus drivers, nurses, etc. get holiday pay, which is recognition that they and their families are sacrificing their personal lives for the good of society. And they are Off after their shift. Maybe I will find a soup kitchen to volunteer for for Christmas, but then I would not be around if the other is not called in. No can do. How many days to Ground Hog Day?